The S enantiomer of 2-hydroxyglutarate increases central memory CD8 populations and improves CAR-T therapy outcome

Cancer immunotherapy is advancing rapidly and gene-modified T cells expressing chimeric antigen receptors (CARs) show particular promise. A challenge of CAR-T cell therapy is that the ex vivo-generated CAR-T cells become exhausted during expansion in culture, and do not persist when transferred back to patients. It has become clear that naive and memory CD8 T cells perform better than the total CD8 T-cell populations in CAR-T immunotherapy because of better expansion, antitumor activity, and persistence, which are necessary features for therapeutic success and prevention of disease relapse. However, memory CAR-T cells are rarely used in the clinic due to generation challenges. We previously reported that mouse CD8 T cells cultured with the S enantiomer of the immunometabolite 2-hydroxyglutarate (S-2HG) exhibit enhanced antitumor activity. Here, we show that clinical-grade human donor CAR-T cells can be generated from naive precursors after culture with S-2HG. S-2HG-treated CAR-T cells establish long-term memory cells in vivo and show superior antitumor responses when compared with CAR-T cells generated with standard clinical protocols. This study provides the basis for a phase 1 clinical trial evaluating the activity of S-2HG-treated CD19-CAR-T cells in patients with B-cell malignancies.